const app = new Vue({
  data: {
    msg: 'hello vue!!!',
    isActive: true,
    hasError: false,
    classObj: {
      active: true,
      'text-danger': false
    },

    activeClass: 'active',
    errorClass: 'text-danger',
    // style
    activeColor: 'red',
    fontSize: 30,
    styleObj: {
      fontSize: '20px',
      'background-color': 'blue'
    },
    styleObj1: {
      display: 'flex',
      alignItems: 'center',
      color: '#0ff'
    }
  },
  computed: {
    classObject() {
      return {
        active: this.isActive,
        'text-danger': this.hasError
      }
    }
  }
}).$mount('#app')
